Noureddine Abouricha^1,*, Ayoub Gounni², Mustapha El Alami²

Frontiers in Heat and Mass Transfer, Vol.22, No.1, pp. 359-375, 2024, DOI:10.32604/fhmt.2024.047632

Abstract In this paper, experimental and numerical studies of heat transfer in a test local of side heated from below are presented and compared. All the walls, the rest of the floor and the ceiling are made from plywood and polystyrene in sandwich form ( plywood- polystyrene- plywood) just on one of the vertical walls contained a glazed door (). This local is heated during two heating cycles by a square plate of iron the width , which represents the heat source, its temperature is controlled. The plate is heated for two cycles by an adjustable set-point heat source placed just… More >

Li Chen, Hui-Bao Luan, Wen-Quan Tao^*

Frontiers in Heat and Mass Transfer, Vol.1, No.2, pp. 1-11, 2010, DOI:10.5098/hmt.v1.2.3002

Abstract Multi-phase lattice Boltzmann method is applied to investigate liquid water transport in th GDL and GC. The liquid water transport processes in the GDL, near the GDL-GC interfaces and in the GC are discussed. The effects of channel land on liquid water dynamic behaviors and distribution in the GDL and GC are investigated. It is found that channel land covers the GDL-GC interface where liquid water reaches changes the water distribution near the GDL-GC interface and in the GC. While channel land is apart from the GDL-GC interface where liquid water reaches changes the effects of channel land is smaller. More >

Noureddine Abouricha^1,*, Chouaib Ennawaoui^1,2, Mustapha El Alami³

Frontiers in Heat and Mass Transfer, Vol.21, pp. 523-537, 2023, DOI:10.32604/fhmt.2023.045914

Abstract This work presents a simulation of the phenomena of natural convection in an enclosure with a variable heating regime by the lattice Boltzmann method (LBM). We consider a square enclosure of side H filled with air (Pr = 0.71) and heated from below, with a hot portion of length L = 0.8 H, by imposing a sinusoidal temperature. The unheated segments of the bottom wall are treated as adiabatic, and one of the vertical walls features a cold region, while the remaining walls remain adiabatic. The outcomes of the two-dimensional (2D) problem are depicted through isotherms, streamlines, the temperature evolution… More >

Siham Hammid¹, Khatir Naima², Omolayo M. Ikumapayi³, Cheikh Kezrane¹, Abdelkrim Liazid⁴, Jihad Asad⁵, Mokdad Hayawi Rahman⁶, Farhan Lafta Rashid⁷, Naseer Ali Hussien⁸, Younes Menni^2,9,*

CMES-Computer Modeling in Engineering & Sciences, Vol.138, No.1, pp. 273-299, 2024, DOI:10.32604/cmes.2023.028951

Abstract The objective of this investigation is to assess the effect of obstacles on numerical heat transfer and fluid flow momentum in a rectangular microchannel (MC). Two distinct configurations were studied: one without obstacles and the other with alternating obstacles placed on the upper and lower walls. The research utilized the thermal lattice Boltzmann method (LBM), which solves the energy and momentum equations of fluids with the BGK approximation, implemented in a Python coding environment. Temperature jump and slip velocity conditions were utilized in the simulation for the MC and extended to all obstacle boundaries. The study aims to analyze the… More >

Rahouadja Zarita^*, Madjid Hachemi

Frontiers in Heat and Mass Transfer, Vol.12, pp. 1-12, 2019, DOI:10.5098/hmt.12.5

Abstract In this work, heat transfer enhancement in a microchannel using water-Ag nanofluid has been investigated numerically by the lattice Boltzmann method (LBM) by adopting the stream and collide algorithm, with the (BGK) approximation. The base fluid and the suspended nanoparticles are considered as a homogeneous mixture. And single phase model with first order slip and jump boundary conditions has been adopted. Thermophysical properties of water-Ag nanofluid are estimated by the theoretical models. Effects of change in nanoparticle volume fractions, Reynolds number and Knudsen number are considered. It was concluded that change in nanoparticle volume fractions did not have significant effects… More >

Romana Basit¹, Xinyang Li¹, Zheqing Huang¹, Qiang Zhou^1,2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.136, No.2, pp. 1509-1526, 2023, DOI:10.32604/cmes.2023.025308

Abstract Direct Numerical Simulations have been carried out to study the forced convection heat transfer of flow through fixed prolate particles for a variety of aspect ratios ar = {5/4, 5/3, 5/1} with Reynolds number (Re) up to 100. Three variations of the solid volume fraction c = {0.1, 0.2, 0.3} with four Hermans orientation factors S = {−0.5, 0, 0.5, 1} are studied. It has been found that changes in S cause prominent variations in the Nusselt number. In general, Nusselt number increases with the decrease of S. For all three aspect ratios, the Nusselt number remains a linear function… More > Graphic Abstract

Xiaokang Tian¹, Kai Yue^1,2,*, Yu You^1,2, Yongjian Niu¹, Xinxin Zhang^1,2

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.2, pp. 301-317, 2021, DOI:10.32604/fdmp.2021.013521

Abstract The heat transfer performances of a microchannel heat sink in the presence of a nanofluid can be affected by the attachment of nanoparticle (NP) on the microchannel wall. In this study, the mechanisms underlying NP transport and attachment are comprehensively analyzed by means of a coupled double-distribution-function lattice Boltzmann model combined with lattice-gas automata. Using this approach, the temperature distribution and the two-phase flow pattern are obtained for different values of the influential parameters. The results indicate that the number of attached NPs decrease exponentially as their diameter and the fluid velocity grow. An increase in the wall temperature leads… More >

T. Ahmed¹, S. Hassan^1,2, M. F. Hasan³, M. M. Molla^1,2,*, M. A. Taher⁴, S. C. Saha⁵

Energy Engineering, Vol.118, No.1, pp. 15-36, 2021, DOI:10.32604/EE.2020.011237

Abstract The magneto-hydrodynamics (MHD) effect is studied at different inclined angles in Rayleigh-Bénard (RB) convection inside a rectangular enclosure using the lattice Boltzmann method (LBM). The enclosure is filled with electrically conducting fluids of different characteristics. These characteristics are defined by Prandtl number, Pr. The considered Pr values for this study are 10 and 70. The influence of other dimensionless parameters Rayleigh numbers Ra = 10³; 10⁴; 10⁵; 10⁶ and Hartmann numbers Ha = 0, 10, 25, 50, 100, on fluid flow and heat transfer, are also investigated considering different inclined angles φ of magnetic field by analyzing computed local Nusselt… More >

Dong Zhou^1,*, Zhuoying Tan²

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.5, pp. 903-917, 2020, DOI:10.32604/fdmp.2020.010363

Abstract In this study, a two-dimensional approach is elaborated to study with the lattice Boltzmann method (LBM) the seepage of water in the pores of a soil. Firstly, the D2Q9 model is selected to account for the discrete velocity distribution of water flow. In particular, impermeability is considered as macroscopic boundary condition for the left and right domain sides, while the upper and lower boundaries are assumed to behave as pressure boundaries controlled by different densities. The micro-boundary conditions are implemented through the standard rebound strategy and a non-equilibrium extrapolation scheme. Matlab is used for the development of the related algorithm.… More >

K. Suga, T. Ito

The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.4, pp. 99-100, 2011, DOI:10.3970/icces.2011.018.099

Abstract Evaluation and optimization of the multiple-relaxation-time (MRT) lattice Boltzmann method for micro-flows (micro-flow LBM) are performed with the two-dimensional nine discrete velocity (D2Q9) model. The MRT micro-flow LBM consisting of the combination of bounce-back and full diffusive (CBBFD) wall boundary condition is considered. Based on the discussion of Chai et al. (2010), the presently applied CBBFD model and relaxation time for heat flux satisfy the second-order slip boundary condition. However, modification to the MRT model of Chai et al. (MRT-C) is made to the relaxation time for the moments related to the stress by introducing the psi function (Stops,1970; Guo… More >